CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (Parentheticals) - shares	12 Months Ended
Jun. 30, 2018	Jun. 30, 2017
Common Class A [Member]
Purchases of shares of Common Stock (class A)	48,947	69,636
Common Class C [Member]
Number of shares converted	90	180
Common Stock [Member] \| Common Class A [Member]
Balance	13,866,601	13,866,421
Balance	13,866,691	13,866,601
Purchases of shares of Common Stock (class A)	48,947	69,636
Issuance of stock under ESPP shares of Common Stock (class A)	2,605	3,433
Number of shares issued as result of stock conversion	90	180
Common Stock [Member] \| Common Class C [Member]
Balance	2,068,947	2,069,127
Balance	2,068,857	2,068,947
Number of shares converted	90	180

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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The number of shares converted in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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The number of new shares issued in the conversion of stock in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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Number of shares issued during the period as a result of an employee stock purchase plan.

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Number of shares that have been repurchased during the period and are being held in treasury.

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